The normalized full gradient (NFG) method defined by Berezkin (1967, 1973 and 1998) is already used for detecting reservoirs. We apply the method for delineating near-surface gravity anomalies. 2-D rectangular prisms with different coordinates are used as the synthetic models to be detected by the method. The NFG is also applied to real microgravity data to determine the place and depth of a subterranean water tunnel (ghanat).